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Thursday, June 21, 2012

At nearly four feet tall, the Emperor penguin is Antarctica’s
largest sea bird. Unlike other sea birds, Emperor penguins breed and
raise their young almost exclusively on sea ice. If global temperatures
continue to rise, the Emperor penguins in Terre Adélie in East
Antarctica may eventually disappear. (Credit: Photo courtesy Glen Grant,
U.S. Antarctic Program, National Science Foundation)

ScienceDaily (June 20, 2012)
— At nearly four feet tall, the Emperor penguin is Antarctica's largest
sea bird -- and thanks to films like "March of the Penguins" and "Happy
Feet," it's also one of the continent's most iconic. If global
temperatures continue to rise, however, the Emperor penguins inTerre
Adélie, in East Antarcticamay eventually disappear, according to a new
study by led by researchers from the Woods Hole Oceanographic
Institution (WHOI).

The study was published in the June 20th edition of the journal Global Change Biology.
"Over the last century, we have already observed the disappearance of
the Dion Islets penguin colony, close to the West Antarctic Peninsula,"
says Stephanie Jenouvrier, WHOI biologist and lead author of the new
study. "In 1948 and the 1970s, scientists recorded more than 150
breeding pairs there. By 1999, the population was down to just 20 pairs,
and in 2009, it had vanished entirely." Like in Terre Adélie,
Jenouvrier thinks the decline of those penguins might be connected to a
simultaneous decline in Antarctic sea ice due to warming temperatures in
the region.

Unlike other sea birds, Emperor penguins breed and raise their young
almost exclusively on sea ice. If that ice breaks up and disappears
early in the breeding season, massive breeding failure may occur, says
Jenouvrier. "As it is, there's a huge mortality rate just at the
breeding stages, because only 50 percent of chicks survive to the end of
the breeding season, and then only half of those fledglings survive
until the next year," she says.

Disappearing sea ice may also affect the penguins' food source. The
birds feed primarily on fish, squid, and krill, a shrimplike animal,
which in turn feeds on zooplankton and phytoplankton, tiny organisms
that grow on the underside of the ice. If the ice goes, Jenouvrier says,
so too will the plankton, causing a ripple effect through the food web
that may starve the various species that penguins rely on as prey.

To project how penguin populations may fare in the future,
Jenouvrier's team used data from several different sources, including
climate models, sea ice forecasts, and a demographic model that
Jenouvrier created of the Emperor penguin population at Terre Adélie, a
coastal region of Antarctica where French scientists have conducted
penguin observations for more than 50 years.

Combining this type of long-term population data with information on
climate was key to the study, says Hal Caswell, a WHOI senior
mathematical biologist and collaborator on the paper.

"If you want to study the effects of climate on a particular species,
there are three pieces that you have to put together," he says. "The
first is a description of the entire life cycle of the organism, and how
individuals move through that life cycle. The second piece is how the
cycle is affected by climate variables. And the crucial third piece is a
prediction of what those variables may look like in the future, which
involves collaboration with climate scientists."

Marika Holland of the National Center for Atmospheric Research is one
such scientist. She specializes in studying the relationship between
sea ice and global climate, and helped the team identify climate models
for use in the study.

Working with Julienne Stroeve, another sea ice specialist from the
National Snow and Ice Data Center, Holland ultimately recommended five
distinct models. "We picked the models based on how well they calculated
the sea ice cover for the 20th century," she says. "If a model
predicted an outcome that matched what was actually observed, we felt it
was likely that its projections of sea ice change in the future could
be trusted."

Jenouvrier used the output from these various climate models to
determine how changes in temperature and sea ice might affect the
Emperor penguin population at Terre Adélie. She found that if greenhouse
gas emissions continue to rise at levels similar to today -- causing
temperatures to rise and Antarctic sea ice to shrink -- penguin
population numbers will diminish slowly until about 2040, after which
they would decline at a much steeper rate as sea ice coverage drops
below a usable threshold.

"Our best projections show roughly 500 to 600 breeding pairs
remaining by the year 2100. Today, the population size is around 3000
breeding pairs," says Jenouvrier.

The effect of rising temperature in the Antarctic isn't just a
penguin problem, according to Caswell. As sea ice coverage continues to
shrink, the resulting changes in the Antarctic marine environment will
affect other species, and may affect humans as well.

"We rely on the functioning of those ecosystems. We eat fish that
come from the Antarctic. We rely on nutrient cycles that involve species
in the oceans all over the world," he says. "Understanding the effects
of climate change on predators at the top of marine food chains -- like
Emperor penguins -- is in our best interest, because it helps us
understand ecosystems that provide important services to us."
Also collaborating on the study were Christophe Barbraud and Henri
Weimerskirch of the Centre d'Etudes Biologiques de Chizé, in France, and
Mark Serreze of the National Snow and Ice Data Center in the United
States.

Tuesday, June 19, 2012

A population of chinstrap penguins is feeling the heat, with more than
one-third of a breeding colony lost in the past 20 years, new research
finds.

A warming planet, which is causing sea ice in Antarctica (and elsewhere) to melt, may ultimately be to blame for the plummeting penguin population,
the researchers said. That's because the chinstraps' main food,
shrimplike creatures called krill, depend on algae that attaches to that
ice.

"Actually, in the '90s it was thought that the climate change would
favor the chinstrap penguin, because this species prefers sea waters
without ice, unlike the Adélie penguin,
which prefers the ice pack," study researcher Andres Barbosa told
LiveScience. He added that at the time, chinstraps, named for the thin
black facial line from cheek to cheek, seemed to increase in numbers,
with some new colonies being established.

The sea-ice decline in the winter, however, has become so big that it
is now impacting krill populations, said Barbosa, of the National Museum
of Natural Sciences in Madrid.

Counting chinstraps

Barbosa and his colleagues tallied chinstrap penguins (Pygoscelis antarctica)
in the Vapour Col colony of Deception Island, in the Antarctic's South
Shetland Islands in 1991-92 and 2008-09. They photographed nests in 19
subcolonies, mainly in December when chicks were hatching.

Results, which ended up including just 12 of the subcolonies due to
availability of data, showed the occupied nests had declined by 36
percent between 1991 and 2008.

Barbosa and colleagues ruled out research activity as the cause for the
loss since both studied populations and those used as controls showed
similar patterns of decline.

Tourism is also not a likely culprit. Deception Island, built on a volcano, is one of the most visited places in Antarctica;
the 2007-08 year saw some 25,000 visitors, according to the
International Association of Antarctica Tour Operators (IAATO).
Meanwhile, the nearby chinstrap penguin colony of Bailey Head, which is
usually visited by 2,000 to 3,500 people every season, showed a decline
of about 50 percent.

Rather, a dip in the krill population may be to blame, an idea supported by the fact that Adélie penguin population (P. adeliae) in the region is also declining, while the gentoo penguin population (P. papua), which has a more variable diet, is not.

(The chinstrap, gentoo and Adélie penguins are the three pygoscelid species (in the Pygoscelis
genus) that inhabit the Antarctic Peninsula, the region of the
Antarctic continent where the effects of climate change are more
evident, the researchers noted.)

Saving penguins

But Barbosa says the chinstraps aren't a lost cause.

"This is an example of how the human activity far from the poles can
affect the life at thousands of kilometers far from our homes," Barbosa
told LiveScience. "Therefore, a more responsible use of the energy and
the fossil fuels is necessary to preserve the planet and then the
Antarctica."

In addition, he said, to protect the organisms that call the Antarctic
home, we need to reduce human impact by reducing overfishing, tourism
and even research activity.

Chin StrapCredit: Andres BarbosaNamed
for the thin black band of feathers that extends from ear to ear under
their heads, chinstrap penguins grow to about 2.2 feet (68 centimeters)
tall, with males being larger and heavier than females.

Two ChicksCredit: Andres BarbosaThe
female usually lays two eggs in a shallow nest in late November, with
each of the pair participating in incubation duties. The chicks hatch
after about 33 to 35 days.

Deception IslandCredit: Andres BarbosaAndres
Barbosa of the National Museum of Natural Sciences in Madrid and his
team have been studying the chinstrap penguins of Deception Island since
1999. Its volcanic origins have shaped the island into a horseshoe
shape, with the volcano's caldera at the center. The island is one of
the most visited of Antarctica, drawing some 25,000 visitors in the year
2007-08.

Find the MateCredit: Andres BarbosaMonogamy
between chinstrap penguin couples often persists from year to year,
with pairs even using the same nesting sites in successive years. To
make sure they've got the right mate, the penguins use certain
mate-recognition behavior, seen here between a pair of chinstraps, which
involves the penguins pumping their chests and stretching their heads
upward.

Little NestsCredit: Andres BarbosaFemale
chinstrap penguins form a circular platform nest with a shallow
interior. The nests are roughly about 16 inches (40 cm) across and up to
6 inches (15 cm) high.

Chick HuddleCredit: Andres BarbosaTypically,
fledgling occurs at about 7 to 8 weeks, with the chinstrap penguin
chicks eventually forming crèches, or groups of young penguins that
huddle together for warmth and protection. Then, at about 50-60 days
old, once the chicks have molted, they head out to sea.

Nest ChecksCredit: Andres BarbosaThe
researchers tallied the occupied nests on the island in 1991-92 and
2008-09. Here they are checking chinstrap nests. (They also used
photographic evidence for nest counts.)

Main FoodCredit: Andres BarbosaThe
culprit for the decline is likely a loss of their main prey, tiny
shrimplike creatures called krill. The krill eat algae that attach to
the sea ice, so without sea ice the krill plummet, followed by a decline
in chinstrap penguins.

Penguins PlummetCredit: Andres BarbosaThe researchers found occupied nests on the island have declined by about 36 percent between 1991 and 2008.

Sea IceCredit: Andres BarbosaSea
ice around the Antarctic's Deception Island. "Actually, in the 90's it
was thought that the climate change would favor the chinstrap penguin,
because this species prefers sea waters without ice unlike the Adelie
penguin which prefers the ice pack," study researcher Andres Barbosa
told LiveScience. The sea-ice decline in the winter, however, has become
so big that it is now impacting krill populations, said Barbosa, of the
National Museum of Natural Sciences in Madrid.

Saving ChinstrapsCredit: Andres BarbosaBut
Barbosa says the chinstraps aren't a lost cause. "This is an example of
how the human activity far from the poles can affect the live at
thousands of kilometers far from our homes," Barbosa told LiveScience.
"Therefore, a more responsible use of the energy and the fossil fuels is
necessary to preserve the planet and then the Antarctica."

Penguin ProtectionCredit: Andres BarbosaIn
addition, he said, to protect the organisms that call the Antarctic
home we need to reduce human impact by reducing overfishing, tourism and
even research activity.source

Monday, June 18, 2012

This artist's rendition created from a photograph of Antarctica
shows what Antarctica possibly looked like during the middle Miocene
epoch, based on pollen fossil data. (Credit: NASA/JPL-Caltech/Dr. Philip
Bart, LSU)

ScienceDaily (June 17, 2012)
— A new university-led study with NASA participation finds ancient
Antarctica was much warmer and wetter than previously suspected. The
climate was suitable to support substantial vegetation -- including
stunted trees -- along the edges of the frozen continent.

The team of scientists involved in the study, published online June 17 in Nature Geoscience,
was led by Sarah J. Feakins of the University of Southern California in
Los Angeles, and included researchers from NASA's Jet Propulsion
Laboratory in Pasadena, Calif., and Louisiana State University in Baton
Rouge.

By examining plant leaf wax remnants in sediment core samples taken
from beneath the Ross Ice Shelf, the research team found summer
temperatures along the Antarctic coast 15 to 20 million years ago were
20 degrees Fahrenheit (11 degrees Celsius) warmer than today, with
temperatures reaching as high as 45 degrees Fahrenheit (7 degrees
Celsius). Precipitation levels also were found to be several times
higher than today.

"The ultimate goal of the study was to better understand what the
future of climate change may look like," said Feakins, an assistant
professor of Earth sciences at the USC Dornsife College of Letters, Arts
and Sciences. "Just as history has a lot to teach us about the future,
so does past climate. This record shows us how much warmer and wetter it
can get around the Antarctic ice sheet as the climate system heats up.
This is some of the first evidence of just how much warmer it was."

Scientists began to suspect that high-latitude temperatures during
the middle Miocene epoch were warmer than previously believed when
co-author Sophie Warny, assistant professor at LSU, discovered large
quantities of pollen and algae in sediment cores taken around
Antarctica. Fossils of plant life in Antarctica are difficult to come by
because the movement of the massive ice sheets covering the landmass
grinds and scrapes away the evidence.

"Marine sediment cores are ideal to look for clues of past
vegetation, as the fossils deposited are protected from ice sheet
advances, but these are technically very difficult to acquire in the
Antarctic and require international collaboration," said Warny.

Tipped off by the tiny pollen samples, Feakins opted to look at the
remnants of leaf wax taken from sediment cores for clues. Leaf wax acts
as a record of climate change by documenting the hydrogen isotope ratios
of the water the plant took up while it was alive.

"Ice cores can only go back about one million years," Feakins said. "Sediment cores allow us to go into 'deep time.'"

Based upon a model originally developed to analyze hydrogen isotope
ratios in atmospheric water vapor data from NASA's Aura spacecraft,
co-author and JPL scientist Jung-Eun Lee created experiments to find out
just how much warmer and wetter climate may have been.

"When the planet heats up, the biggest changes are seen toward the
poles," Lee said. "The southward movement of rain bands associated with a
warmer climate in the high-latitude southern hemisphere made the
margins of Antarctica less like a polar desert, and more like
present-day Iceland."

The peak of this Antarctic greening occurred during the middle
Miocene period, between 16.4 and 15.7 million years ago. This was well
after the age of the dinosaurs, which became extinct 64 million years
ago. During the Miocene epoch, mostly modern-looking animals roamed
Earth, such as three-toed horses, deer, camel and various species of
apes. Modern humans did not appear until 200,000 years ago.

Warm conditions during the middle Miocene are thought to be
associated with carbon dioxide levels of around 400 to 600 parts per
million (ppm). In 2012, carbon dioxide levels have climbed to 393 ppm,
the highest they've been in the past several million years. At the
current rate of increase, atmospheric carbon dioxide levels are on track
to reach middle Miocene levels by the end of this century.

High carbon dioxide levels during the middle Miocene epoch have been
documented in other studies through multiple lines of evidence,
including the number of microscopic pores on the surface of plant leaves
and geochemical evidence from soils and marine organisms. While none of
these 'proxies' is as reliable as the bubbles of gas trapped in ice
cores, they are the best evidence available this far back in time. While
scientists do not yet know precisely why carbon dioxide was at these
levels during the middle Miocene, high carbon dioxide, together with the
global warmth documented from many parts of the world and now also from
the Antarctic region, appear to coincide during this period in Earth's
history.

This research was funded by the U.S. National Science Foundation with
additional support from NASA. The California Institute of Technology in
Pasadena manages JPL for NASA.

Story Source:

The above story is reprinted from materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Sunday, June 10, 2012

'Depraved' sex acts by penguins shocked polar explorer

Scientists now understand the biological reasons for behaviour Dr Levick considered to be "depraved"

Accounts
of unusual sexual activities among penguins, observed a century ago by a
member of Captain Scott's polar team, are finally being made public.

Details, including "sexual coercion", recorded by Dr George
Murray Levick were considered so shocking that they were removed from
official accounts.
However, scientists now understand the biological reasons behind the acts that Dr Levick considered "depraved".

The Natural History Museum has published his unedited papers.
Dr Levick, an avid biologist, was the medical officer on
Captain Scott's ill-fated Terra Nova expedition to the South Pole in
1910. He was a pioneer in the study of penguins and was the first person
to stay for an entire breeding season with a colony on Cape Adare.
He recorded many details of the lives of adelie penguins, but
some of their activities were just too much for the Edwardian
sensibilities of the good doctor.

He was shocked by what he described as the "depraved" sexual
acts of "hooligan" males who were mating with dead females. So
distressed was he that he recorded the "perverted" activities in Greek
in his notebook.

Graphic account

On his return to Britain, Dr Levick attempted to publish a
paper entitled "the natural history of the adelie penguin", but
according to Douglas Russell, curator of eggs and nests at the Natural
History Museum, it was too much for the times.
"He submitted this extraordinary and graphic account of
sexual behaviour of the adelie penguins, which the academic world of the
post-Edwardian era found a little too difficult to publish," Mr Russell
said.

Pages from Dr Levick's notebook with some sections coded in Greek

The sexual behaviour section was not included in the official
paper, but the then keeper of zoology at the museum, Sidney Harmer,
decided that 100 copies of the graphic account should be circulated to a
select group of scientists.
Mr Russell said they simply did not have the scientific
knowledge at that time to explain Dr Levick's accounts of what he termed
necrophilia.

"What is happening there is not in any way analogous to
necrophilia in the human context," Mr Russell said. "It is the males
seeing the positioning that is causing them to have a sexual reaction.
"They are not distinguishing between live females who are
awaiting congress in the colony, and dead penguins from the previous
year which just happen to be in the same position."Sexual coercion

Only two of the original 100 copies of Dr Levick's account
survive. Mr Russell and colleagues have now published a
re-interpretation of Dr Levick's findings in the journal Polar Record.
Mr Russell described how he had discovered one of the copies by accident.
"I just happened to be going through the file on George
Murray Levick when I shifted some papers and found underneath them this
extraordinary paper which was headed 'the sexual habits of the adelie
penguin, not for publication' in large black type.

"It's just full of accounts of sexual coercion, sexual and
physical abuse of chicks, non-procreative sex, and finishes with an
account of what he considers homosexual behaviour, and it was
fascinating."
The report and Dr Levick's handwritten notes are now on
display at the Natural History Museum for the first time. Mr Russell
believes they show a man who struggled to understand penguins as they
really are.

"He's just completely shocked. He, to a certain extent, falls
into the same trap as an awful lot of people in seeing penguins as
bipedal birds and seeing them as little people. They're not. They are
birds and should be interpreted as such."

Gay, straight or necrophiliac, a penguin isn't a human being

By Tim StanleyScienceJune 9th, 2012

All ages of man have tried to understand penguin sexuality in human terms

An Edwardian notebook has gone on display
at the Natural History Museum that describes the sexual activities of
the Antarctic penguin. Read it and you’ll never look at Pingu the same
way again.
The text was compiled by George Murray Levick, a scientist with the
Scott Antarctic Expedition, and it contains details of homosexuality,
pederasty, necrophilia and rape. In the Antarctic summer of 1911-1912,
Levick observed the breeding cycle of the Adélies colony at Cape Adare.
To his horror, he witnessed male penguins attempting to make love to the
long-dead bodies of females, males getting it on with other males, and
coercive sex acts with females and chicks that sometimes led to violence
and death. It was Sodom in the snow.

It’s hardly news that penguins are motivated entirely by their loins, but what reports
have seized upon is the charming way in which Levick processed this
information. Being an Edwardian gentleman, he blamed the orgy on the
male “hooligans,” perhaps believing that the lady penguins were
incapable of bad behaviour. Describing what he saw as “astonishing
depravity,” he recorded it all in Greek code and his findings were
suppressed for many years. Reading Levick’s work, it’s hard not to spot
traces of Judeo-Christian morality that seem inappropriate in the
context of zoological study. Anything that an animal does cannot be
depraved because they don’t have morals, or a rational soul.

But the temptation towards Anthropomorphism (the identifying of human
characteristics among animals) didn’t stop in the Edwardian era. We
still do it today – rationalising animal sexual behaviour in a
different, yet still heavily politicised, way.

Take the case of the gay penguins. Inca and Rayas
met at the Faunia Park in Madrid and seemed so devoted to each other
that the zookeepers gave them their own egg. The pair have been dubbed
“gay” and elevated to the status of the Elton and David of the animal
kingdom. They are proof, for those seeking it, that gay monogamy finds a
template in nature.

The problem is that the term “gay” is as inappropriate to describe
what’s going on here as is Levick’s use of “depravity.” Gay is a term
that has only been in use since the rights revolution of the 1960s and
which describes far more than just homosexual activity; it denotes a
politicised identity that makes no sense unless it is self-aware and
publicly understood. Levick’s penguins face no moral choices, so they
cannot be depraved. Inca and Rayas cannot conceptualise sexual category
or identity, so they can’t be gay in the sense that a human being is.
They certainly can't go through the rite of passage associated with
being gay, "coming out." The thought of them waddling up to their
parents – flipper in flipper – and telling them to prepare themselves
for a shock is absurd.

Indeed, their zookeeper insists that they are not even homosexual –
just “the best of friends.” There’s every expectation that they will,
eventually, mate with a female. That’s happened in Tornoto,
where the star “gay” couple, Buddy and Pedro, was paired off with
females. The “bromance” was over when Buddy made it with a girl called
Farai. Pedro chased the luscious Thandiwey for several weeks, but got
nowhere. Buddy and Pedro’s relationship was never sexual, but instead
social. That didn’t stop people asking if it was “homophobic” to separate them, as if some fundamental human right was being broken.

And what is happening here is the projection of human values onto a different species.
At the same time that we more ruthlessly exploit animals than ever
before, we also seem determined to find qualities within them that we
can empathise with. We want to turn them into mirrors of ourselves.
Sometimes – as with the Dachshund UN
– the result is unbelievably cute. But in most instances it misleads
about the nature of animals and blurs the lines between man and nature.
Humanity shouldn’t judge its moral code by the sexual standards of the
penguins. It should be guided by the uniquely human qualities of reason
and compassion.